Stronger Bell Inequalities for Werner states?
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Find Bell Inequalities which are stronger than the CHSH inequalities in the sensethat they are violated by a wider range of Werner states.
In 2003, Daniel Collins and Nicolas Gisin  found a Bell Inequality and states which violate the new but not the CHSH inequalities. Alas, the range of Werner states violating the new inequality is smaller than that for the CHSH setting.
- D. Collins, N.Gisin, quant-ph/0306129 (2003)